Bypass surgery versus stenting for the treatment of multivessel disease in patients with unstable angina compared with stable angina.

BACKGROUND: Earlier reports have shown that the outcome of balloon angioplasty or bypass surgery in unstable angina is less favorable than in stable angina. Recent improvements in percutaneous treatment (stent implantation) and bypass surgery (arterial grafts) warrant reevaluation of the relative merits of either technique in treatment of unstable angina. Methods and Results- Seven hundred fifty-five patients with stable angina were randomly assigned to coronary stenting (374) or bypass surgery (381), and 450 patients with unstable angina were randomly assigned to coronary stenting (226) or bypass surgery (224). All patients had multivessel disease considered to be equally treatable by either technique. Freedom from major adverse events, including death, myocardial infarction, and cerebrovascular events, at 1 year was not different in unstable patients (91.2% versus 88.9%) and stable patients (90.4% versus 92.6%) treated, respectively, with coronary stenting or bypass surgery. Freedom from repeat revascularization at 1 year was similar in unstable and stable angina treated with stenting (79.2% versus 78.9%) or bypass surgery (96.3% versus 96%) but was significantly higher in both unstable and stable patients treated with stenting (16.8% versus 16.9%) compared with bypass surgery (3.6% versus 3.5%). Neither the difference in costs between stented or bypassed stable or unstable angina ($2594 versus $3627) nor the cost-effectiveness was significantly different at 1 year. CONCLUSIONS: There was no difference in rates of death, myocardial infarction, and cerebrovascular event at 1 year in patients with unstable angina and multivessel disease treated with either stented angioplasty or bypass surgery compared with patients with stable angina. The rate of repeat revascularization of both unstable and stable angina was significantly higher in patients with stents.

Influence of the two-stage anatomic correction of simple transposition of the great arteries on left ventricular function.

To evaluate the influence of the 2-stage anatomic correction of simple transposition of the great arteries on left ventricular (LV) function, pressure and angiocardiographic volume data were analyzed during resting conditions shortly before banding of the pulmonary trunk (n = 12) and before (n = 17) and after anatomic correction (n = 11), and compared with data from controls (n = 12). Age at banding and anatomic correction was between 1 and 44 months (mean 16 +/- 10) and between 13 and 47 months (mean 24 +/- 10), respectively. The interval between anatomic correction and the investigation ranged from 10 to 29 months (mean 20 +/- 7). After banding, LV ejection fraction decreased (p less than 0.01) and LV peak systolic pressure (p less than 0.01) as well as LV end-diastolic pressure (p less than 0.05) increased. After anatomic correction, these variables and LV end-systolic wall stress were not significantly different from control values. The LV end-systolic wall stress-ejection fraction relation in 7 of 11 patients after anatomic correction was within control range. The highest values were found in the youngest patients at banding and at anatomic correction. In contrast to measures of global myocardial function, such as LV ejection fraction and LV end-diastolic pressure data, the LV end-systolic stress-ejection fraction relation suggest that LV function may not be normal in some patients 20 months after anatomic correction. Young age at operation, however, appears to be advantageous in preserving LV function. Hemodynamic alterations after banding probably reflect LV adaptation to systemic pressures in a hypoxemic circulation.

Short-term hemodynamic results after right ventricular outflow tract reconstruction using a cusp-bearing transannular patch.

Correction of right ventricular outflow tract obstruction remains a challenge to cardiovascular surgeons. In order to relieve this obstruction and at the same time prevent or minimize pulmonary insufficiency, we inserted a cusp-bearing transannular patch (monocusp) in 14 patients. To test this objective, we restudied 13 of these patients 0.5 to 4 months postoperatively, including quantifying pulmonary insufficiency using an accurate videodensitometric method. In all patients a degree of pulmonary insufficiency ranging from 8% to 46% of total stroke volume (mean 22.7 +/- 10.6%) was measured, and in all but one a residual right ventricular outflow pressure gradient of 2 to 22 mm Hg (mean 10 +/- 7 mm Hg) was measured. There was an inverse relation between the degree of pulmonary insufficiency and both the pressure gradient (r = -0.89) and the ratio of the pulmonary valve ring diameter to monocusp depth (r = -0.67). An ideal reconstruction of the right ventricular outflow tract obstruction, without any postoperative pulmonary insufficiency and stenosis, was not achieved by the implantation of a monocusp in the described fashion. The postoperative results were acceptable in only a few patients. A reduction of pulmonary insufficiency seems to be associated with a small residual pressure gradient as well as a relatively small cusp size. Additional studies are necessary to further improve surgical correction of right ventricular outflow tract obstruction with reproducible and predictable results.

Examination of hemolytic potential with the On-X(R) prosthetic heart valve.

BACKGROUND AND AIM OF THE STUDY: Mechanical valves are known to produce chronic, subclinical hemolysis in most patients. Generally, haptoglobin is reduced to below normal in most patients, while lactate dehydrogenase (LDH) is increased to as much as 200% above the upper normal, sometimes resulting in anemia. The study was designed to investigate the clinical hemolysis of the On-X(R) prosthetic heart valve in a multicenter experience with a standard protocol and a single clinical laboratory. METHODS: Between September 1996 and August 1998, 248 patients underwent isolated valve replacement at 10 European centers. Blood samples were collected from these preoperatively and at 3-6 months and one year postoperatively. All samples were analyzed at a central laboratory, thus assuring poolability of the data. In total, 151 patients were tested at 3-6 months, and 62 at one year. Blood parameters measured were LDH, haptoglobin, hematocrit, total hemoglobin, red cell count and reticulocyte count. Paired analysis was used to compare preoperative baseline values with 3-6-month and one-year values. Data were analyzed with regard to both valve position and size. RESULTS: At 3-6 months and one year after surgery, average values for hematocrit, hemoglobin, red cell count and reticulocyte count were all near the center of the normal range, regardless of valve position or size. Statistically significant increases in red cell count and decreases in reticulocyte count occurred after both aortic valve replacement (AVR) and mitral valve replacement (MVR). These changes were of no clinical importance, but indicate that anemia has not occurred in these patients. At 3-6 months, haptoglobin was reduced to below normal in 86% of both AVR and MVR patients; this also occurred after one year and was statistically significant. Postoperatively, the mean LDH value in AVR was 228 U/l (91% of upper normal, 250 U/l) at 3-6 months, and 246 U/l (98% of upper normal) at one year. In MVR, these LDH values were 271 U/l (108% of upper normal) and 265 U/l (106% of upper normal). CONCLUSIONS: These results indicate that the On-X valve causes lower levels of chronic hemolysis in the immediate postoperative period and up to one year after surgery, especially when compared with reports of LDH elevations up to 200% of upper normal. Hemolytic anemia has not occurred in this patient population.

Early clinical experience with the On-X prosthetic heart valve.

BACKGROUND AND AIM OF THE STUDY: The study was designed to investigate the clinical performance of the On-X prosthetic heart valve in a multicenter experience. METHODS: Between September 1996 and September 1999, 301 patients (56% males) underwent isolated On-X valve replacement (184 isolated aortic (AVR), 117 isolated mitral (MVR)) at 11 European centers under a standardized protocol. Average age at implant was 60.2 years. Office or hospital follow up was required by the protocol; average follow up on all patients was 11 months. RESULTS: Thirty-day mortality in the study was 2.2% for AVR and 6.0% for MVR, with valve-related mortality of 0.5% for AVR. There were eight late deaths (0.7%/pt-yr AVR and 2.3%/pt-yr MVR). Two of these deaths were sudden, and thus possibly valve-related (one AVR, one MVR). Early total valve-related morbidity was 3.5% for AVR and 2.6% for MVR. In total, 13 thromboembolic events occurred; one early event in AVR resulted in death (0.5%), and one transient early event occurred in MVR (0.9%). There were 11 late events (seven AVR (1.7%/pt-yr) and four MVR (1.8%/pt-yr)), for a two-year freedom from thromboembolism of 96.6% after AVR and 97.1% after MVR. Three late bleeding events occurred, all after AVR (0.7%/pt-yr and 98.9% free at two years). Major paravalvular leaks requiring reoperation occurred on two occasions early (one AVR (0.5%), one MVR (0.8%)) and once late in MVR (0.5%/pt-yr). Late minor, untreated paravalvular leaks occurred in three AVR patients (0.7%/pt-yr) and in one MVR patient (0.5%/pt-yr). Prosthetic endocarditis occurred four times (two AVR (0.5%/pt-yr), two MVR (0.9%/pt-yr)), all within the first 12 months of surgery. Actuarial freedom from all valve-related events at two years was 88.7% for AVR and 88.1% for MVR. NYHA class was improved in 75.8% of AVR patients and 70.6% of MVR patients at two years after surgery. CONCLUSION: These early results indicate that the On-X valve provides satisfactory clinical outcome in the immediate postoperative period, and that the valve is both safe and effective.

Gene transfer into rat heart-derived endothelial cells.

OBJECTIVE: Progressive graft arteriosclerosis is responsible for the majority of late deaths in cardiac transplant recipients. Despite many investigations, the pathogenesis of this disease remains undetermined and its control inadequate. A somatic gene transfer during the cold ischemic time and thus before transplantation might be a new therapeutic tool. This approach allows a long incubation time of the DNA and a safe transfer with liposomes and transferrin with less adverse effects for the organ recipient. METHODS: The target cells (microvascular endothelial cells (MVECs)) for this gene transfer were isolated from rat hearts by perfusion with collagenase via an aortic cannulae. The cells were purified by changing the medium 30 min after subcultivation in order to remove fibroblasts and smooth muscle cells. The endothelial cells (ECs) were identified by typical morphology and the uptake of Dil-Ac-LDL. The gene transfer was carried out with a beta-galactosidase reporter plasmid (pCMVbeta), cationic liposomes (Lipofectin), and transferrin. Different transfection solutions were prepared with or without serum, and with different plasmid-liposome ratios and transferrin concentrations. The transfer rate was monitored with a semiquantitative orthonitrophenyl-beta/-D-galactoside (ONPG) assay and histologically by X-Gal staining. The cytotoxicity of this procedure was determined with a colorimetric ELISA with Alamar blue. The cardioplegic property of the transfection solution was tested in a Langendorff perfusion system monitoring the coronary blood flow over time after a cold ischemic time of 4 h. RESULTS: The maximal gene expression could be detected after transfection with 4 microl Lipofectin, 2 microg pCMVbeta, and 16 microg transferrin/200 microl transfection solution. Under these conditions 60% of the cells showed a blue staining with X-Gal. Only 20% of the cells died during transfection. The lowest cytotoxicity during cold ischemic time for ECs was assessed with normal cell culture medium and the Buckberg solution. The best coronary flow rates after 4 h cold ischemia of the heart were measured for cardioplegia with St. Thomas and Buckberg solutions. In summary, the best transfection solution with a good cardioplegic property was the Buckberg solution. CONCLUSIONS: Finally, the results of this study show that an effective DNA delivery with a low toxicity into ECs is possible with a combination of liposomes and transferrin. This method might be useful for a safe and effective gene transfer into solid organs during the cold ischemic time and thus a therapeutic tool for chronic rejection.

Long-term results after surgical correction of atrioventricular septal defects.

OBJECTIVE: Review of the results of surgical correction of atrioventricular septal defects (AVSD), identification of risk factors for mortality and failure of left AV valve repair and determination of the impact of cleft closure on postoperative AV valve function. METHODS: Between 1975 and 1995, 121 consecutive patients (55 males, 66 females) underwent surgery for biventricular correction of AVSD with a median age of 1.2 years and a median weight of 7.6 kg. Sixty-five patients had a complete AVSD, 17 patients an intermediate type, and 39 patients a partial AVSD. The left AV valve (MV) cleft was closed in 53 patients (43.8%). The mean follow-up time is 7.2+/-4.6 years. RESULTS: Actuarial survival of the whole group after 1 year was 80%, after 10 and 20 years 78 and 65%, respectively. There were 18 early deaths (7-day mortality, 10.7%; 30-day mortality, 14.9%) and eight late deaths. In a univariate analysis, risk factors for early or late death were diagnosis of complete AVSD (P=0.006), no cleft closure (P=0.024), postoperative complications (P<0.0001), age <1.2 years (P=0.017), weight <7.6 kg (P=0.002), PA/Ao pressure ratio >0.7 (P<0.0001), and ECC time >110 min (P=0.002). In the multivariate analysis, postoperative complications (P=0.003) and PA/Ao pressure ratio >0.7 (P=0.001) had parallel effects on the postoperative risk for mortality. Moderate or severe MV regurgitation was present in six patients (6.0%) in the first evaluation after discharge and in 20 patients (20.4%) in the most recent postoperative control. There were 25 reoperations in 17 patients, of which 15 had to be performed for MV regurgitation and two for MV stenosis. Freedom from reoperation was 91% at 1 year, 79% at 10 years, and 76% at 15 and 20 years. We could not identify a statistically significant risk factor for reoperation. CONCLUSIONS: In patients with AVSD of various morphologies closure of the left AV valve cleft significantly improves outcome without affecting the need for reoperation. Risk factors for early and late death (multivariate analysis) were a pulmonary/aortic pressure ratio >0.7 and the occurrence of any complication after surgery. The concept of an early surgical AVSD correction before an increase in pulmonary vascular resistance and AV valve deformations occur would represent a better surgical option than a late correction as done in our series. Early correction allows for reduction of early mortality, superior long-term survival rates and a high freedom from subsequent valve degeneration.

[Modified manual rt-PA pulse-spray lysis in occlusions of leg arteries and femoro-popliteal bypasses]. / Modifizierte manuelle rt-PA Puls-Sprüh-Lyse bei Beinarterien- und femoropoplitealen Bypass-verschlüssen.

PURPOSE: The evaluation of local rt-PA pulse-spray-lysis (PSL) by the Katzen infusion wire for treatment of thrombosed leg arteries and bypass grafts. MATERIAL AND METHOD: 21 patients (mean age 64.4 years) with either occluded leg arteries (n = 19) or femorocrural bypass grafts (n = 2) were treated with PSL. Mean length of occlusion was 13.2 +/- 11.6 cm. Time of occlusion ranged from less than one week to 6 months. RESULTS: In 71.43% (15/21) the occlusions could be successfully recanalized with PSL. The mean rt-PA dose was 10.7 +/- 4.9 mg. Remaining stenoses were handled with PTA (n = 9) and additional stent implantation (n = 3). Additional long-time-lysis with 17.5 mg rt-PA was necessary in two cases, the success rate increased to 81% (17/21). The anlde-brachial-index increased from 0.38 +/- 0.29 to 0.83 +/- 0.32 within 24 hours after intervention. In 4 cases bleeding complications occurred. 5 patients showed reocclusions during 6 months follow-up. CONCLUSIONS: Local fibrinolysis with rt-PA in PSL technique using the Katzen infusion wire is a feasible and promising treatment of thrombosed leg arteries and grafts. Even careful and dosage-minimized rt-PA application cannot prevent bleeding complications.

Aortic valve reconstruction in Rubinstein-Taybi-syndrome: the valuable aid of transesophageal echocardiography.

A fourteen year old boy with Rubinstein-Taybi-syndrome presented with a severe congenital subvalvular fibrous aortic stenosis with associated aortic regurgitation. Transthoracic echocardiographic imaging and left heart angiography showed a transvalvular peak systolic pressure gradient of 90 mmHg and a regurgitant fraction of 30%. The surgical treatment consisted of resection of the subvalvular fibrous tissue and subsequent aortic valvuloplasty. Intraoperative transesophageal echocardiography revealed a wide systolic opening of the aortic valve and good coaptation of the aortic valve leaflets in diastole. Two-dimensional color-coded and contrast echocardiography were successfully used to confirm a satisfactory reconstruction. Transesophageal echocardiography therefore represents a valuable tool in the assessment of the morphologic and haemodynamic status, especially in rare cases of congenital heart disease in older children.

Divalent ions and myocardial function during cardiopulmonary by-pass (CPB). Changes of total calcium, ionized calcium, and magnesium in plasma.

In 17 patients who underwent openheart surgery with cardiopulmonary bypass using heparinized fresh blood for priming the heart-lung machine the following investigations were done: Blood samples taken at different periods of surgery were assayed for total calcium (Catot), ionized calcium (Ca++), magnesium (Mg), hemoglobin, total pasma proteins, and the acid-base-status. Considering the different kinds of cardiopulmonary bypass the patients were divided into three groups: In the first group the results ofsurgical procedure with and without hemodilution perfusion were compared. During hemodilution perfusion Catot decreased markedly whereas Ca++ remained nearly constant. In the second group the influence of different calcium concentrations of the prime solution on Catot and Ca was tested. A low calcium content of 2.8 mEq/1 lowered Catot and Ca++ to subnormal levels. In the third group results of Mg-induced cardioplegia were compared with findings during surgical procedure with anoxic cardiac arrest. A remarkable increase of magnesium at the perfusion onset could be observed. Magnesium remained within the upper level of normal range until surgery end and decreased to normal values in the postoperative stage. Since energy requirements of the arrested heart and thus the velocity of ATP-breakdown during ischemia are closely related to the Ca++ concentration of the extracellular space low plasma calcium levels are considered to be advantageous during cardiopulmonary bypass. Only at the end of partial bypass before the heart fully takes over circulating work a sufficient calcium substitution is recommended.

Multiple organ manifestations in thromboangiitis obliterans (Buerger's disease). A case report.

Thromboangiitis obliterans (TAO) occurs almost exclusively in young male smokers. Its involvement of the small and medium-sized arteries and veins leads to ischemic complaints and/or changes in the extremities. The possibility of organ involvement is a matter of controversy. The authors report a case of TAO with multiple organ involvement, including myocardial, splenic, and cerebral infarctions; pulmonary embolisms; and probable intestinal ischemia during a twenty-three-year course.

Bacterial and fungal infections after cardiac surgery in children.

Of 245 children operated on for congenital heart diseases in 1983-1984, bacterial and fungal infections occurred in 3.6% compared to 17.8% of 469 in 1968-1972. Staphylococcal infections decreased from 3.4%-0.8% and those by gram-negative bacteria from 6.9%-0%; Candida albicans infections increased from 0%-1.2%. Perioperative prophylaxis was performed with cefotaxime plus piperacillin in 1983-1984 versus oxacillin plus ampicillin in 1968-1972. It is argued that reduction of the infection rate is not only due to newer and more effective antibiotics but is mainly related to more advanced surgical techniques and improved hygiene in our intensive care units.

Effects of enoximone on right-ventricular function in patients with impaired myocardial performance.

The effects of an enoximone monotherapy on left-ventricular and especially on right-ventricular haemodynamics were investigated in fourteen patients with impaired left-ventricular function secondary to coronary artery disease. Anaesthesia was induced and maintained with fentanyl and flunitrazepam. After reaching steady state, a bolus of 0.5 mg/kg enoximone was administered, followed by an infusion of 0.5 microgram/kg/min. Besides the common haemodynamic parameters particulary the right-ventricular ejection fraction (RVEF) was measured using a special thermodilution technique. The predefined time points were: before administration of enoximone (baseline) and 5 min, 10 min, 15 min, 20 min, and 30 min after bolus injection of enoximone. Compared to the baseline the maximum effects of enoximone were a 28% increase of cardiac index accompanied by a 39% decline of systemic vascular resistance and an unchanged left-ventricular stroke-work index. While central venous pressure and mean pulmonary artery pressure remained unchanged. RVEF (+20%) and right-ventricular stroke-work index (+30%) were significantly augmented, augmented, indicating improved right-ventricular performance. No adverse effects of the enoximone administration were observed perioperatively. We conclude that an enoximone monotherapy is beneficial for patients with impaired myocardial function undergoing cardiac surgery.

[The portacaval anastomosis (author's transl)]. / 12. Die portacavale Anastomose

All patients treated in the authors' clinic for portal hypertension from 1958 to 1975 are reviewed and the problems encountered with portacaval anastomoses are explained with special reference to encephalopathy and hepatic failure. Intrahepatic block was recorded in 88% of 722 patients. Portacaval anastomoses were constructed in 292 cases, splenorenal anastomoses in 175, and mesenterico-caval anastomoses in 12. Among the patients with stationary cirrhosis, the 6-year survival was unrelated to the type of operation performed and amounted to approximately 70%, while 6-year survival was only 40% in patients with progressive cirrhosis of the liver, whether they received surgical or conservative treatment.

[Surgical treatment of critical aortic isthmus stenosis in infancy]. / Chirurgische Behandlung der kritischen Aortenisthmusstenose im Säuglingsalter.

Early and late results of 43 infants (35 under 3 months of age) who underwent different surgical repairs (29 Waldhausen subclavian flap method, 11 resection and end-to-end-anastomosis, 1 Clagett method, 2 Goretex patch) for coarctation of the aorta during the years 1970-1982 are reported. Only one patient had isolated coarctation, five patients had coarctation with patent duct (PDA). Associated cardiac anomalies were found in 37 patients. 17 (39,5%) infants died early after surgery. All were under 3 month of age with severe cardiac anomalies (16x intracardiac, 1x PDA). There were two late deaths after correction of intracardiac defects. In 6 out of 24 surviving patients restenosis developed 1-10 years after repair (3 of 6 patients with end-to-end-anastomosis = 50%, 2 of 10 patients with subclavian flap method = 20%, 1 patient with Goretex-patch). Our results show that coarctation with associated cardiac anomalies in patients under 3 month present higher surgical risk. Subclavian flap technique ist the method of choice for preductal coarctation. Technical difficulties related of this method are discussed in detail.

[Coarctation of the aorta: surgical management in infancy--results in 72 patients (author's transl)]. / Chirurgische Behandlung der Aortenisthmusstenose im Säuglingsalter - Ergebnisse von 72 Patienten.

Early and late results of a total of 72 infants operated for coarctation of the aorta are reported. Operative repair included various methods (End-to-End, Vossschulte, Clagett, Shumaker, Waldhausen, Blalock). Isolated coarctation was present in 6 infants, 17 also had patent ductus arteriosus, 39 patients had additional associated cardiac anomalies, part of which were combined with PDA. Out of the 72 infants 17 died (early mortality: 11, late mortality: 6). The highest mortality rate was found among the 0 to 3 months age group (11 patients). Fourteen out of the 17 deceased patients had additional cardiac anomalies. Out of the 55 survivals, 37 patients showed good results, restenosis was found in 13 patients, 5 patients had to be reoperated due to severe restenosis.

[Traumatic aortic rupture: immediate surgery--interval operation?]. / Traumatische Aortenruptur: Sofortoperation--Intervalloperation?

On the basis of our own patient population of the last 12 years which involved 17 traumatic ruptures of the descending thoracic aorta in the isthmus area (preoperative hospital mortality at the time of diagnosis: 5.8%; surgical mortality: 27%; postoperative hospital mortality: 18.7%) the problems of assessing indications for surgical intervention in polytraumatized patients with aortic damage are discussed. The indications for "immediate surgery", for "surgery with delayed urgency", and for "surgery in the interval" are clearly defined.

Early neurological abnormalities following coronary artery bypass surgery. A prospective study.

A prospective analysis of 78 patients undergoing coronary artery bypass surgery (CABS) was carried out to assess clinically the frequency and course of cerebral complications during the 1st postoperative week. Detailed evaluation of the patients showed that neurological abnormalities after CABS were common, occurring in 40 of the 78 patients (51%). However, there were no serious cerebral complications. Changes in reflexes and new focal signs were found in 26 and 25 cases respectively; in 7 patients (9%) they were confined to the first postoperative days. There was no statistically significant correlation between postoperative outcome and age, preoperative neurological state or bypass time. However, some strong associations could be calculated between a history of cerebrovascular signs or symptoms and the appearance of persisting focal signs or development reflexes during the 1st week after CABS.